Hello,
Can someone explain the basic differences between the dynamax fan and the byron fan please? Do each accept different engines?

two different animals that both use the os 91 most commonly

byron is a ~6" pusher, high static thrust, lower top end. less critical ducting, engine pipe parts sit in front of the fan

dynamax is a ~5" tractor, little lower static, higher top end , more critical ducting, engine pipe parts sit behind

Pat
Thanks for the reply.
The only other question, will either of these fans accept the Rossi 61 or 81?
Dave

yes,

they had unique centerbodies (engine mounts) for the os or rossi or k&b, so it might take some hunting, but I have seen them mounted in both.